Backup Exec 2010 R3 Exchange 2007 MAPI Issue

[Ameril01]

We are having an issue with our backups failing when backing up our Exchange DB.  The wierdest thing is it works and succesfully backs up Exchange for three to four days straight and then one day will fail out.  The same error shows up with each fail:

The job failed with the following error: Cannot log on to MAPI with the specified credentials. Review the resource credentials for the job, and then run the job again.

How can the same credentails work one night and not the other?

Thank You.

[ZeRoC00L]

Check all possible solutions in this technote:

http://www.symantec.com/business/support/index?page=content&id=TECH64095

[Ameril01]

Since it works most of the time, I don't see how it could be any of the issues listed in that document.  I have gone through the steps in that document, but have had no luck in fixing the issue.

[Ameril01]

We have had two solid weeks of successful backups.  Last night our backup decided to fail with the MAPI error again.  How can it work completly successful and then all of a sudden fail?

[Norbert72]

You will find the reason in this article.

http://www.symantec.com/business/support/index?page=content&id=TECH172067